Photoelectrocatalytic oxidation provides a technically applicable way for solar-chemical synthesis, but its efficiency and selectivity are moderate. Herein, a microfluidic photoelectrochemical architecture with 3-D microflow channels is constructed by interfacial engineering of defective WO₃/TiO₂ heterostructures on porous carbon fibers. Kelvin probe force microscopy and photoluminescence imaging visually evidence the charge accumulation sites on the nanojunction. This efficient charge separation contributes to a 3-fold enhancement in the yield of glyceraldehyde and 1,3-dihydroxyacetone during glycerol upgrading, together with nearly doubled production of high value-added KA oil and S₂O₈²⁻ oxidant through cyclohexane and HSO₄⁻ oxidization, respectively. More importantly, the microfluidic platform with enhanced mass transfer exhibits a typical reaction selectivity of 85 %, which is much higher than the conventional planar protocol. Integrating this microfluidic photoanode with an oxygen reduction cathode leads to a self-sustained photocatalytic fuel cell with remarkably high open-circuit voltage (0.9 V) and short-circuit current (1.2 mA cm⁻²).

光电催化氧化为太阳能化学合成提供了一种技术上适用的方法，但其效率和选择性中等。在此，通过对多孔碳纤维上的有缺陷的WO ₃ / TiO ₂异质结构进行界面工程来构建具有3-D微流通道的微流体光电化学结构。开尔文探针力显微镜和光致发光成像在视觉上证明了纳米结上的电荷积累部位。这种高效的电荷分离有助于甘油升级期间甘油醛和1,3-二羟基丙酮的收率提高3倍，同时高附加值KA油和S ₂ O ₈ ^2-的产量几乎翻倍。通过环己烷和HSO氧化剂₄ ^-分别氧化。更重要的是，具有增强的传质能力的微流体平台具有典型的85％的反应选择性，这比常规的平面实验方案要高得多。将该微流体光阳极与氧还原阴极结合在一起，得到具有非常高的开路电压（0.9V）和短路电流（1.2mA cm ^-2）的自持式光催化燃料电池。